

DIGESTIBILITY OF CEREAL BREAKFAST FOODS. 193 
cereal alone which was actually available (85.32 per cent.) is 
then obtained by subtracting from the total energy in the 
cereal (3,127 calories) the estimated energy in the feces from 
the cereal (381 calories) and the energy lost in the urine 
(62.34 — 1.25=) 78.0 calories, and dividing this result by the 
total energy in the cereal consumed (3,127 calories). 
DATA OF THE EXPERIMENTS. 
In these experiments no attempt was made to have the quan- 
tities of the different food materials the same for all the sub- 
jects, nor even for the same subject from meal to meal. Each 
subject ate according to his appetite at each meal, weighing 
his own food from the same lot as the others, just before eating. 
The weighings were made on a sensitive torsion balance, and 
one subject checked the weights taken by another, to insure 
accuracy. | 
Some of the subjects, from choice, endeavored to maintain 
the total quantity of the cereal per day the same throughout 
an experiment, and in some cases the quantity per meal was 
uniform for a given day. In the case of the milk and cream 
there was in general less uniformity in amount, though in at 
least one case this was the same for each meal of the whole 
experiment. Each subject poured some milk or cream into a 
vessel, used what he wanted at the meal, and determined the 
amount from the weight of the vessel and contents at the begin- 
ning and end of the meal. Sugar was treated in the same 
way, except that the weight of the bottle and the sugar was 
taken at the beginning and end of the experiment, so that the 
quantity eaten per meal or per day is not known. 
The total quantity of each food material eaten in the different 
experiments is shown in the table below. The last column 
shows the average quantities per day; but it will be observed, 
from what is explained above, that these do not, in some cases, 
show the amount that was actually eaten per day. ‘These latter 
figures are given for the cereal part of the diet in connection with 
the data of the experiment beyond. 
